21870403850 has 12 divisors (see below), whose sum is σ = 40678951254. Its totient is φ = 8748161520.

The previous prime is 21870403843. The next prime is 21870403859. The reversal of 21870403850 is 5830407812.

It can be written as a sum of positive squares in 3 ways, for example, as 20831437561 + 1038966289 = 144331^2 + 32233^2 .

It is not an unprimeable number, because it can be changed into a prime (21870403859) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 218703989 + ... + 218704088.

Almost surely, 2^21870403850 is an apocalyptic number.

21870403850 is a deficient number, since it is larger than the sum of its proper divisors (18808547404).

21870403850 is a wasteful number, since it uses less digits than its factorization.

21870403850 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 437408089 (or 437408084 counting only the distinct ones).

The product of its (nonzero) digits is 53760, while the sum is 38.

The spelling of 21870403850 in words is "twenty-one billion, eight hundred seventy million, four hundred three thousand, eight hundred fifty".